Non-pneumatic spare tire

Abstract

An improved nonpneumatic tire for a motor vehicle is described. The tire has a rim and one or more elastomeric materials bonded to the rim or to one another. The tire has an equatorial plane, an annular tread rotatable about an axis, and an annular elastomeric body. The elastomeric body has at least 48 openings, a first set of at least 24 openings extend from the first side and a second set of at least 24 openings extend from a second side, both sets extending toward the equatorial plane. The openings form equally spaced columns. The columns formed by the first set of openings are inclined to the radial direction. The columns formed by the second set of openings are inclined opposite to the columns of the first set. The improved tire is characterized by columns having cross sections equidistant from the equatorial plane. The cross section of each of the columns increases in thickness from a minimum to maximums at the radially inner and radially outer extremes of the column.

What is claimed is: 
     
       1. An improved nonpneumatic tire of the type having a rim and one or more elastomeric materials bonded to the rim or to one another, the tire having an equatorial plane, an axis perpendicular to the equatorial plane, an annular tread rotatable about the axis, an annular elastomeric body made from a material having a Shore A hardness in the range of 60 to 100, the body having first and second spaced lateral sides equidistant from the equatorial plane and extending between the tread and the rim, the body having at least 48 openings positioned equidistant from the axis, at least 24 of which extend from the first side and at least 24 of which extend from the second side to form first and second sets of openings extending from the respective sides toward the equatorial plane, the openings forming equally-spaced columns of elastomeric material in the body, the columns formed by the first set of openings being generally inclined to the radial direction of the tire, the columns formed by the second set of openings being generally inclined to the radial direction of the tire but opposite in inclination with respect to the columns formed by the first set of openings, the improved tire being characterized by: the columns of the first and second set sets having respective cross-sections, the cross-sections of the columns of the first set having a minimum thickness t1s1 located radially inwardly of the tread and radially outwardly of a radially innermost portion of the annular body, t1s1 being measured as a line passing through the circumferential centerline of the openings and being the shortest distance between adjacent openings of the first set, the thickness of the columns of the first set increasing as they extend radially outwardly from the minimum thickness t1s1 to a maximum radially outer thickness t2s1 at a radially outermost portion of the columns of the first set, t2s1 being measured along a line that is tangent to the radially outer extremes of adjacent openings, and the thickness of the columns of the first set increasing as they extend radially inwardly from the minimum thickness t1s1 to a maximum radially inner thickness t3s1 at a radially innermost portion of the column as measured along a line that is tangent to the radially inner extremes of adjacent openings, and the ratio of t2s1 to t1s1 and the ratio of t3s1 to t1s1 both being at least 150% in the cross-section, the cross-section of the columns of the second set having a minimum thickness t1s2 located radially inwardly of the tread and radially outwardly of a radially innermost portion of the annular body, t1s2 being measured as a line passing through the circumferential centerline of the openings and being the shortest distance between adjacent openings of the second set, the thickness of the columns of the second set increasing as they extend radially outwardly from the minimum thickness t1s2 to a maximum radially outer thickness t2s2 at a radially outermost portion of the columns of the second set, t2s2 being measured along a line that is tangent to the radially outer extremes of adjacent openings, and the thickness of the columns of the second set increasing as they extend radially inwardly from the minimum thickness t1s2 to a maximum radially inner thickness t3s2 at a radially innermost portion of the column as measured along a line tangent to the radially inner extremes of adjacent openings and the ratio of t2s2 to t1s2 and the ratio of t3s2 to t1s2 both being at least 150% in the cross-section and wherein the openings of the first set communicate with the openings of the second set, the openings taper downwardly as the openings extend axially inwardly, the openings having a maximum size at a side of the tire.   
     
     
       2. The tire of claim 1, wherein the columns of the first set intersect the columns of the second set when the respective cross-sections are overlaid, the intersection of columns being at at least one location per column. 
     
     
       3. The tire of claim 2, wherein the intersection of columns is located closer to the radially inner portion of the columns of both sets than to the radially outermost portion of the columns. 
     
     
       4. The tire of claim 2, wherein each of the columns of one set intersect columns of the opposite set at only two locations, the first intersection being located at about the radially innermost portion of a column and the second intersection being located at about the radially outermost portion of a column. 
     
     
       5. The tire of claim 1, wherein the columns formed by the first set of openings intersect the columns formed by the second set of openings at locations other than in the equatorial plane of the tire. 
     
     
       6. The tire of claim 2, wherein the columns formed by the first set of openings intersect the columns formed by the second set of openings at locations other than in the equatorial plane of the tire. 
     
     
       7. The tire of claim 3, wherein the columns formed by the first set of openings intersect the columns formed by the second set of openings at locations other than in the equatorial plane of the tire. 
     
     
       8. The tire of claim 4, wherein the columns formed by the first set of openings intersect the columns formed by the second set of openings at locations other than in the equatorial plane of the tire. 
     
     
       9. The tire of claim 1, each of the openings comprising an elliptical curvature having a major and minor axis. 
     
     
       10. The tire of claim 2, each of the openings comprising an elliptical curvature having a major and minor axis. 
     
     
       11. The tire of claim 3, each of the openings comprising an elliptical curvature having a major and minor axis. 
     
     
       12. The tire of claim 4, each of the openings comprising an elliptical curvature having a major and minor axis. 
     
     
       13. The tire of claim 5, each of the openings comprising an elliptical curvature having a major and minor axis. 
     
     
       14. The tire of claim 9 wherein the minor axis is offset from the midpoint of the major axis. 
     
     
       15. The tire of claim 12 each of the openings comprising an oval curvature. 
     
     
       16. The tire of claim 1 each of the openings comprising an oval curvature. 
     
     
       17. The tire of claim 14 having a ratio of major axis to minor axis greater than 1:1. 
     
     
       18. The tire of claim 1 wherein the tread portion comprises a first resilient material and the elastomeric body comprises a second resilient material. 
     
     
       19. The tire of claim 1, wherein each opening of the first set communicates with an opening of the second set at a radially inner portion of the openings. 
     
     
       20. The tire of claim 19, wherein each opening of the first set communicates with a pair of openings of the second set. 
     
     
       21. The tire of claim 20, wherein each opening of the second set communicates with a pair of openings from the first set.